Coating or decorating apparatus



Feb. 7, 1939. I V, CASTQ 2,145,861

COATING 0R DECORATING APPARATUS Filed June 13, 19:55 2 Sheets-Sheet 1 H I H 1 s P ,/6 2* a 6 B A: 5 /z 9 0 o o o l0 1 u v 4 V QIIJVENTOR. I

BY LLOYD V C4570 ATTORNEYS Feb. 7, 1939; 1 v c s-ro I 2,145,861

COATING OR DECORATING APPARATUS Filed June 13, 1955 2 Sheets-Sheet 2 INVENTOR. F1 6 BY [Lona V C'Asfo fiwz, yr/M4, 77M

ATTORNEYS at... Feb. ,1, 1939' PATENT oFFlca ooa'rmeon naooaarme mourns Lloyd v. Caste, mm, mm". Application June 13, 1935. Serial No. ra n 4 Claims; (CI. 91-45) This invention relates to spray coating apparatus'for applying varnish and lacquer for example,

and particularly to improvements in automatic I apparatus by which blanks are coated successivelylwhile supported on a suitable conveyor. I The principal object is to provide a coating apparatus operable'to controllably apply coats'of lacquer, varnish, etc. with predetermined unevenness.i

- A further object is to provide an improved apparatus for applying decorative and/or protective coatings to blanksin a-manner to controllably vary the reflecting effects of the surfaces coated.

nism which may be easily and quickly adjusted to varythe periodof projecting or spraying alternately heavy and lightcoatings on a single blank.

Other objects and features of the invention will become. apparent from the following description relating to the accompanying drawings, showing the preferred form.

"In thedrawings, Fig. 1 is a diagram showing a complete apparatus including the spray gun hereof, support therefor, and conveying apparatus or mechanism for blanks to be coated; Figs. 2 and 3 are diagrammatic sectional views (greatly enlarged) showing the effects it is desired to prodine on a blank with the present arrangement;

Fig. 4 is'a sectional side'elevation of a known type of spray gun for varnish, lacquer, etc., the

novel parts of the mining shown in side eleva-- tion;-Fig. 5' is-an enlarged sectional fragmentary plan view of the motor and gearing arrangement in'place on the gun; Fig. 6 is a side elevation of lthe motor and gearing unit shown in place on g the gun-in Fig. 5, and Figs. '1 and 8 illustrate difierent forms of cams that may be used on the apparatus shown in Fig. 4.

f'wood, metal, etc., as ordinarily finished by paint, varnish, lacquer or enamel, ii in compara- 'tively large panels, presentsunbroken highlights be effected in a convenient and practicable way without requiring attention on the part of the operator.

. As shown in Fig. 1, a suitable form of spray gun is illustrated at I, and this may be mounted as on a horizontal bar 2, which is in turn, carried on a vertically shiftable carriage 3 supported on guides conventionally shown at I. The

bar is adapted to extend through a clamping device 5 on top of the gun body, as shown particularly in Fig. 5.

Beneath the gun supporting parts just described, is a conveyorbelt 6, the support for which may comprise rollers I and l, at least one being a drive roller, and the drive roller may be provided with an adjustable driving means such as an adjustable V pulley assembly 8 and In to vary the speed of the work past the gun. Suitable mechanism for driving one element of the V- pulley assembly may comprise a motor and reduction gearing conventionally illustrated at H. The conveyor belt may be provided with suitable driving lugs l2 for carrying the blanks B to and past the gun. .With this arrangement, the gun may be moved different distances from the work, the angle at which the coating material is projected onto the panel may be varied as desired, and as will later be more fully shown the coating supplied to the panel or work B will be alternately thick and thin, as shown in Figs. 2 and 3, at C.

'Referring now to Fig. 4, this shows a general frame or 'body member I! for the gun, which body is made hollow and provided with attachment adapters l6 and," for supply hose or conduits lia and Ma respectively for fluid coating material and a suitable atomizing medium such as air. The air hoseconnection is shown only in Fig.5.

The spray nozzle 20 may be of any. known or suitable type and is located at one end of the body and comprises a head 2| having generally conical orifices, one surrounding the other, and which, through suitable passages 22 and 23, communicate respectively with the coating material hose and the air hose- Additional lateral air passages 24 (on an adjustable head 24a which is turned at right angles to the position shown foroperation in the present arrangement) convert the atomized stream into fan form for covering a comparatively wide area. The liquid coating material is-metered at the orifice of the nozzle by a needle valve2I projecting into the nozzle orifice and its character and operation will be more fully hereinafter described.

It is to be understood that any suitable means at 3B straddling the stem of the valve "and Asshowmthegunbodyllisintwoms'jorparts Ila and ilb and material metering valve is entirely by the may be salvaged bymeans not shown and used bodypartiaainsuitablebores. The'bodypart lob surmounts the'part "a and the air pas-- sages thereof are, controlled by a plunger valve 28 therein cooperating with a valve seat 21, the valve stem having an operating part it protecting rearwardly from the body to suitable control means to be hereinafter described. The air To control the valves, a common lever is shown at H, pivoted as at 3 3 to the body part use. The upper end of the lever has an arm as, a portionof which engages the part," of the air valve, and'below the pivot the lever hasarms adapted to engage an abutment member 3| thereon to open the valve 25 by the same motion which opens the air valve 1'. An adjustable screw 30 is shown in Figs. 4 and 5 for separately controlling the air valve to hold it in predetermined open positions continuously for purposes which will later be more apparent.

The arrangement for automatically adjusting the valves or one of the valves, as the case may require, during operation of the gun, comprises,

as shown, a motor and reduction unit, generally indicated at ll. This comprises an air motor II, a gear unit 42, and a driven shaft ll to which suitable cams. N are removably connected for operating the valve control lever I8.

The cam 44, as'shown in Fig. 4, has two high points and two low points, and these successively engage a suitable follower surface 3! on an upstanding arm ll of the lever. when the cam follower surface is on the low portions of the cam, both. valves are ordinarily slightly cracked; and as the high portions of the cam ride against the follower, the valves are opened more fully, and thus during the continued operation of the motor and gearing the gun sprays the coating medium first heavily and then lightly, twice for 5 ,each complete rotation of. the shaft II, with the particular form of cam shown;

With the cam arrangement of Fig. 7, showing:

an irregular arrangement of checks and hollows, the coating is laid onto the'panel in alternately thick and thin bands vor areas, but these vary in width and thickness, in accordance with the irregularities of the cam surfaces. cam of Fig. 8 merely effects one change in the thickness of the coating for each complete rotation of the shaft ll. Y

may be employed t'ocontrol the essential passageways from the air hose'to the air discharge nos-. zle and from the coating material hose to its nos- 'zle orifice or orifices.

, shown).

The

amass: I

shown as a 1 coupling. This form of motor operates at very high speed. The used all may be discharged through-a suitable duct [5 in a boss l. on the casing. the duct being under the control of a suitable adjustment screw ll by which the speed of the motor may be varied by controlling the back pressure. The exhaust air in the spray gun.

The gearing illustrated comprises an internal type of low reduction gear, the impeller shaft of the motor having an eccentric end portion at ll, forming a planetary support for a pinion 60 meshing with a fixed reactance internal gear 6| and also with a driven internal gear 62 connected with the cam shaft (integral therewith, as The internal gears are of the same pitch but have a different number of teeth, say

a diflerence of one tooth, sothat a low reduction is obtained.

The cams may be interchangeably mounted on I the end of the cam shaft which is shown as square and provided with internal threads for receiving a cam attaching cap screw 64'.

It is sometimes desirable to automatically vary only the feed of fluid coating medium as by the use of the mechanism above described. In such event the air valve 26 is initially set as by means of the adjustable screw 30, the lower edge of which is adapted to bear on an abutment shoulder 28a of the air valve so as to hold the valve part 28 in spaced relation to the actuating arm of the maincontrol lever 33. The invention contemplates similarly independently controlling the coating fluid valve, as by adjustment of the abutment member" on the stem of the valve 25.

It will be seen from the above description that the unpleasant highlight effects on coated surfaces may be broken up by the use of the apparatus in anydesired fashion all without requiring attention on the part of the operator once the various parts are properly adjusted.

I claim:

1. In coating apparatus, means to feed blanks continuously in one direction at a uniform rate, a spray gun in fixed operative relation to said means during operation thereof and arranged to spray a coating of material on said blanks while moved past the same, and mechanism on the gun controlling its operation in predetermined cycles to cause it to spray relatively thick and thin vol- .umes of coating material-on the blanks as the same are movedpast the spraying zone of said gun.

2. A spray gun having a. variable nozzle discharge orifice to govern the rate of discharge of evenbut continuous coating.

3. In decorating apparatus, comprising a. spray gun, and a support for work blanks to be decorated by the gun, means adapted and arranged to move-the support and gun relative to each other continuously at a uniform rate, means to maintain the spray gun in a single operative relationship to the support during such relative movement, and mechanism on the gun which controls its operation in predetermined cycles to cause the gun to spray relatively thick and thin volumes of coating material on the individual blanks during such relative movement of the support and gun.

4. vIn a decorating apparatus, a conveyor arranged to move, at a uniform rate, work blanks auasu 3 to be coated, a relatively fixed support adjacent angles relative to work on the conveyor surface;

the conveyor, a spray gun mounted on the sup- 1 and mechanism connected with the gun in a port and movable thereon toward and away from manner to cause it to spray relatively think and the supporting surface of the conveyon'a con-/ thin layers of coating material on the individual motion between the gun and the support so arblanks, during said movement thereof by the uranged that the gun can be directed for the disconveyor.

charge of coating material at various operating j I LLOYD V. CA BTQ 

